摘要
洞庭盆地水资源供需矛盾日益突出,为查明区域地下水年龄以及循环更新情况,2021年在洞庭盆地资江流域采集浅层地下水氚(3H)和CFCs水样各12组.利用活塞流(PFM)模型对地下水3H和CFCs年龄进行了计算.结果表明:研究区地下水年龄自山前丘岗区至平原区逐步变老.山前丘岗区地下水年龄普遍<40 a,新水补给比例为96.36%~86.41%,地下水实际流速为2.18 m/d,地下水循环更新较快;平原区地下水年龄基本都在50 a以上,新水补给比例为37.09%,地下水实际流速在1.2~1.59 m/d,渗透流速为0.0008~0.0012 m/d,地下水循环更新慢.结合区域水文地质条件,山前丘岗区主要发育局部水流系统,平原区开始进入中间水流系统,平原中部地下水年龄超过80 a,可能与区域循环系统相重叠.
The contradiction between supply and demand of water resources in Dongting basin has become increasingly prominent.In order to evaluate the age,circulation and renewal of groundwater,12 groups water samples of tritium(3H)and CFCs were collected from shallow groundwater in Zijiang basin of Dongting basin in 2021.The piston flow(PFM)model was used to calculate the 3H and CFCs ages of groundwater.The results show that the groundwater age in the study area gradually ages from the piedmont hilly area to the plain area.In the piedmont hilly area,the groundwater age is generally less than 40 years,the recharge ratio of fresh water was 96.36%-86.41%,the actual flow rate of groundwater is 2.18 m/d,and the groundwater circulation renewal was fast.The age of groundwater in plain area is above 50 years,the proportion of new water recharge is 37.09%,the actual groundwater flow rate is 1.2-1.59 m/d,and the infiltration flow rate is 0.0008-0.0012 m/d.The groundwater cycle renewal is slow.Combined with the regional hydrogeological conditions,the piedmont hilly area mainly developed local water flow system,and groundwater in the plain area belongs to the intermediate water flow system.The groundwater age in the central plain is more than 80 years,which may overlap with the regional circulation system.
作者
常致凯
马斌
李静
梁杏
付鹏宇
曹明达
张志鑫
杜永昌
Chang Zhikai;Ma Bin;Li Jing;Liang Xing;Fu Pengyu;Cao Mingda;Zhang Zhixin;Du Yongchang(School of Environmental Studies,China University of Geosciences,Wuhan 430078,China)
出处
《地球科学》
EI
CAS
CSCD
北大核心
2023年第11期4256-4269,共14页
Earth Science
基金
国家自然科学基金项目(No.41772268)
中国地调局项目(Nos.DD20190263,2019040022).
